This invention relates to the field of article storage and retrieval, and more specifically to apparatus adapted for the storage of a variety of descreet articles in a relatively compact space, the apparatus having provisions to allow the rapid and systematic retrieval of a selected group of such articles. More specifically, the invention provides a control system for an article storage and retrieval unit whereby the unit can be moved in response to operator commands to provide access to a selected group of articles.
In many types of retail sales activity there is a requirement for the seller to have on hand a large variety of related but nonidentical goods. For example, a paint seller must have available a variety of different colored paints; a hardware seller a variety of nails, screws and other fasteners of different types and sizes; and a pharmacist a variety of drugs used in filling prescriptions. These items may require a large amount of storage space, and are frequently stored on long rows of shelves arranged horizontally and vertically in a particular area of the seller's place of business. Storage of this type has inherent inefficiencies both in terms of space requirements and in terms of ease of retrieval of any selected article within the group.
The problem is exemplified in the operation of a modern pharmacy. In such an installation, the pharmacist must have a vast quantity of different prescription drugs available to him. The drugs and other pharmaceuticals must be stored in a manner that will allow the pharmacist to easily retrieve any particular item, and in a manner occupying a minimum of space.
A retrieval unit designed to fulfill the foregoing requirements is shown in the U.S. Patent Application, Ser. No. 423,556, filed Dec. 11, 1973, and assigned to the present assignee. Such a unit has the general configuration of a cylinder having its axis of rotation vertically oriented. The cylinder may be divided into a plurality of segments or stations, each station having a suitable arrangement of shelves on which articles may be stored. It is desirable to have such a unit move in rotary motion to provide ready access to any selected segment, without the necessity for the operator to walk around the unit.
When a storage unit of the type described is used in a pharmaceutical application, many of the articles stored therein will be bottles and jars which are small and lightweight. It is therefore important that the unit be capable of starting and stopping its rotation in a smooth manner so that the articles are not tipped and spilled as a result of the rotational acceleration and deceleration of the unit.
It is an object of the present invention to provide a control system for a rotatable storage unit that allows the unit to be rotated through a selected number of degrees of rotation on command of an operator.
Another object of the invention is to provide a control system for a rotatable storage unit having a plurality of stations whereby the control system assures rotation of the unit from one station to another via the shortest available path.
A still further object of the invention is to provide a control system for a rotatable storage unit whereby the unit can be quickly and rapidly rotated from one position to another without abrupt starting and stopping.
Yet another object of the invention is to provide a control system for a rotatable storage unit wherein the control system is relatively small and compact.
These and other objects of the invention will be discussed in further detail and will in part become apparent as the specification proceeds.